The present invention relates to an automobile gear transmission driven by an internal combustion engine, and more particularly to a gear assembly adapted to the gear transmission for eliminating gear knocking noises in operation.
As is well known, gear knocking noises occur in the gear transmission due to inevitable fluctuation of the engine rotation and backlash of the assembled gears. Such gear knocking noises occur most noticeably during idling of the engine when gear transmission is in neutral. For the purpose of eliminating the gear knocking noises, a gear assembly has been proposed which includes a pair of driving and driven gears permanently in meshing engagement with each other to provide a torque transmission therebetween, and an additional gear relatively rotatable at one side of either one of the gears and being permanently in meshing engagement with the other gear to rotate at a gear ratio different from that of the driving and driven gears, and in which the additional gear is resiliently in contact with one end face of the gear adjacent thereto to restrain a relative rotation between the driving and driven gears. In such a gear assembly, the additional gear is mounted on a hub projection of the gear adjacent thereto and is resiliently pressed against the one end face of the gear by engagement with a compression spring, which is arranged in surrounding relationship with the hub projection of the gear and positioned in place by a snap ring on a portion of the hub projection. For this reason, it has been necessary to provide an annular groove in a portion of the hub projection during the hub cutting process and so that the snap ring may be provided in the annular groove.